My own split/overlay image.

Processing details:
1) resample to 50% size
2) 2 passes gaussian filter
3) resample to 200% size
4) 1 pass gaussian filter
i.e. maintain orig. size but get smooth version
4) Import to ER Mapper
5) Rotate 70 degrees anticlockwise
6) Generate mirror-image copy
7) Overlay original (green) with mirror (red)
Comments: The left side of the image shows the differences more clearly, but mathematically the same things are there on the right, but in green.
Note the huge red bow-shock ahead of the left wing and the turbulent trail behind it.
The quality of the overlay is shown by the not-quite-perfect colour fringes around the rest of the shuttle.
Feel free to copy, save, and pass on providing attribution given to USAF and myself.